Rumaki is the main antagonist of the Hi Hi Puffy AmiYumi segment "Secret Origin" and a recurring enemy in the videogame The Genie and the Amp.
He was voiced by Will Ryan.
Rumaki kidnapped tons of visitors of Camp Youwannasushi, Japan and forced them to mine rock candy. He has a giant army of dust monkeys.
Rumaki took Yumi, Ami and Atchan from their bunk beds. Atchan was told by Ami to act like his favorite superhero, which didn't surprise Rumaki. Atchan threatened to Rumaki about his superpowers, which made Rumaki surrender and give his campers back to the surface.
The Genie & The Amp
For some reason, he rose to the surface in an alternate reality where an evil Ami and Yumi rule the earth.
Rumaki is green-furred and has seven appendages that act as both arms and legs.
Grim Adventures of Billy & Mandy